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      <h2><a href="./">Go by Example 中文版</a>: 退出</h2>
      
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            <p>使用 <code>os.Exit</code> 可以立即以给定的状态退出程序。</p>

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            <a href="http://play.golang.org/p/ImcwmsrT8A1"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
          <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
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          <div class="highlight"><pre><span class="kn">import</span> <span class="p">(</span>
    <span class="s">&quot;fmt&quot;</span>
    <span class="s">&quot;os&quot;</span>
<span class="p">)</span>
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          <div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
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            <p>当使用 <code>os.Exit</code> 时 <code>defer</code> 将<em>不会</em> 被执行，
所以这里的 <code>fmt.Println</code> 将永远不会被调用。</p>

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          <div class="highlight"><pre>    <span class="k">defer</span> <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;!&quot;</span><span class="p">)</span>
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            <p>退出并且退出状态为 3。</p>

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          <div class="highlight"><pre>    <span class="nx">os</span><span class="p">.</span><span class="nx">Exit</span><span class="p">(</span><span class="mi">3</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>

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            <p>注意，不像例如 C 语言，Go 不使用在 <code>main</code> 中返回一个整数来指明退出状态。
如果你想以非零状态退出，那么你就要使用 <code>os.Exit</code>。</p>

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            <p>如果你使用 <code>go run</code> 来运行 <code>exit.go</code>，那么退出状态将会被 <code>go</code> 捕获并打印。</p>

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          <div class="highlight"><pre><span class="gp">$</span> go run exit.go
<span class="go">exit status 3</span>
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            <p>通过编译并执行一个二进制文件的方式，你可以在终端中查看退出状态。</p>

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          <div class="highlight"><pre><span class="gp">$</span> go build exit.go
<span class="gp">$</span> ./exit
<span class="gp">$</span> <span class="nb">echo</span> <span class="nv">$?</span>
<span class="go">3</span>
</pre></div>

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            <p>注意，程序中的 <code>!</code> 永远不会被打印出来。</p>

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